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University of Minnesota Extension

Apple maggots

Quick facts 

  • The most important insect pest of Minnesota-grown apples is the apple maggot (Rhagoletis pomonella).
  • Appears in early July and is active until September. Peak activity occurs from late July through early August.
  • Heavily infested fruit is distorted and inedible, but can be used for cider or animal feed.
  • There are nonchemical and chemical options for managing apple maggots.
A black fly with black markings on its clear wings
Apple maggot adult female

How to identify apple maggot

A whitish larva inside an apple with brown, rotting pulp
Apple maggot larva

The adult fly is 1/4 inch long, smaller than a common housefly.

  • It has dark markings on the clear wings and a conspicuous white spot where the thorax joins the abdomen.
  • Has three (male) or four (female) white stripes on the abdomen.

Life cycle of apple maggot

A black fly-like insect on a green apple
Apple maggot adult

Adult apple maggots begin to emerge from the soil starting around July 1, continuing through most of the summer.

  • Adult flies often leave and feed outside the orchard, in wooded or brushy areas.
  • They return to lay eggs just under the skin of apples.
  • Each female fly can lay hundreds of eggs.
  • Once eggs hatch, larvae feed for three to four weeks.
  • When apples drop to the ground, the larvae transform into pupae in the soil.
  • Pupae spend the winter underground, emerging as adults the following summer.

Damage caused by apple maggot

An apple with brown rotting pulp
Inside of an apple with apple maggots
  • Apple maggot flies lay eggs in fruit and the fruit becomes pitted and misshapen.
  • Each "sting” or hole created by the female fly as she lays an egg, forms a tiny spot or dimple.
  • Pulp breaks down, discolors and starts to rot as a result of maggots (larvae) tunneling through the flesh.
  • Larvae are rarely seen.

How to protect your trees from apple maggots


Authors: Jeffrey Hahn, Michelle Grabowski, Jill MacKenzie and Marissa Schuh

Reviewed in 2022

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